$ { \left[\begin{array}{rrr}{4} & {3} & {-1} \\ {1} & {3} & {4}\end{array}\right]+\left[\begin{array}{rrr}{3} & {1} & {-1} \\ {1} & {2} & {1}\end{array}\right] = {?} } $
To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rrr}{4}+{3} & {3}+{1} & {-1}+{-1} \\ {1}+{1} & {3}+{2} & {4}+{1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{7} & {4} & {-2} \\ {2} & {5} & {5}\end{array}\right]}$